The present invention relates to a new and improved construction of apparatus for butt connecting plies of plastic deformable material, if desired containing reinforcement inserts, especially rubberized steel cord plies, and also pertains to a novel method for such butt connecting of plies.
During the production of endless plies it is necessary to join together individual ply elements with one another into a continuous web. There is known to the art a method and apparatus for the butt connection of flexible strips, wherein both ends of the strips, which previously have been rendered adhesive, are connected by an elastic element which tangentially acts upon the ends. The drawback of this known apparatus resides in the great technological expenditure which is required. Thus, apart from the clamping plates which are needed for fixing the strips, there are also necessary devices for moving such clamping plates, an elastic membrane, as well as devices for stressing and relieving such membrane, and also lengthwise guides for the strips. This complicated construction renders the equipment extremely subject to malfunction. Also what is disadvantageous for this technique is the fact that the strips must be rendered adhesive. This can be carried out by applying a binder or by electrical, chemical or thermal treatment. In any event, there is necessary an additional working step and additional equipment. Furthermore, with this prior art technique there is not realized any smooth surface at the butt joints or locations, rather there are present irregularities, damming-up of the material and inhomogeneities. Also disadvantageous with this state-of-the-art procedure is that this technique only can be carried out with strips of very small width, since when using strips of greater width there only can be obtained an insufficient tangential action by the elastic elements, so that the strips cannot be sufficiently rigidly connected with one another.
Moreover, there is known to the art an apparatus for the production of an endless fabric band with wire cores or inserts which are arranged at an angle. This equipment comprises a splicing table, supports, infeed components, components for moving and depositing the band as well as a cutting device and magnetic holding devices. When using this equipment it is possible to obtain a good fixation of the fabric bands which are to be connected, but the connection itself of such fabric bands must be manually performed. Consequently, working with this equipment requires a great deal of time and there is not insured for the necessary accuracy.